Container sealing system

ABSTRACT

An easily closable and openable container system includes a number of features which facilitate easy opening and closing while maintaining a high seal. In a first embodiment, the opening forces can be concentrated on one narrow side which includes a lip on one side of a lid flange and with an angled portion on the opposite side of the flange to give ease of opening with less force involved. In a second embodiment where one side is not significantly shorter than a longest side, the lid flange is located at a corner to concentrate the leverage for opening. A continuous flange surrounds a generally planar member and mates with a outwardly projecting rim. The flange includes a pair of surfaces, including an inwardly angled surface which acts to form a stable seal, and actually urges the lid downward as the natural sealing force from the flange is applied.

FIELD OF THE INVENTION

The present invention relates to a number of advantageous structures and devices for safe, convenient, easy to open and close containment sealing systems which are ideal for preserved sealing, particularly for foodstuffs.

BACKGROUND OF THE INVENTION

Sealed containers are typically used in conjunction with food and other materials to be protected from moisture and the environment, or used with liquids and are to be isolated from spillage. Most sealed containers commercially available have compromised the sealing engagement in order to facilitate a snap shut closure. Quick engagement structures don't typically produce as strong of a seal as a more extended seal with significant sealing forces. Conversely, a good seal typically involves a complex locking arrangement or an extended seal. However, most complex locking arrangements or extended high pressure seals are inconsistent with ease of use and low expense.

The need for an efficient and easily operable seal is especially needed with respect to food containers which may be subjected to microwave use. The failure to form a lid hugging seal can cause containers holding the heated food to explode in the microwave causing damage and a mess. The instant container includes a superior seal as well as a pressure relief valve to that it can be employed to maximum effect in a microwave to insure that the lid stays on. If the pressure exceeds the pressure rating of the safety/pop valve assembly, which will typically be far less than the pressure necessary to dislodge the sealed lid, the safety/pop valve assembly will open to enable gaseous pressure to subside.

SUMMARY OF THE INVENTION

An easily closable and openable container system includes a number of features which facilitate easy opening and closing while maintaining a high seal. In a first embodiment, the opening forces can be concentrated on one narrow side which includes a lip 41 on one side of a lid flange and with an angled portion on the opposite side of the flange to give ease of opening with less force involved. In a second embodiment where one side is not significantly shorter than a longest side, the lid flange is located at a corner to concentrate the leverage for opening.

A continuous flange surrounds a generally planar member and mates with a outwardly projecting rim. The flange includes a pair of surfaces, including an inwardly angled surface which acts to form a stable seal, and actually urges the lid downward as the natural sealing force from the flange is applied. A second surface, below the inwardly angled surface, is the first beveled surface which has sufficient angle to enable the upper part of the upper wall to engage and be urged into position with respect to the inwardly angled surface, and without the user having to provide stretching or two handed operation. In essence, the second surface is beveled to engage the upper wall and enable a mechanically advantaged force to fit the flange over the upper rim of the upper wall so that the sealing surfaces can be brought stably together with simple downward pressure.

The lateral sectional details of the flange portion include a number of angular relationships which contribute to the ease of use and positivity of sealing of the containers illustrated. A differential width flange can also provide additional ease of manipulation at a preferred point of opening.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention, its configuration, construction, and operation will be best further described in the following detailed description, taken in conjunction with the accompanying drawings in which:

FIG. 1 illustrates a perspective view of a rectangular container with a lid in place and illustrating the extended lip, pop valve and top configuration;

FIG. 2 is a sectional view taken along line 2-2 of FIG. 1 and illustrates further details of the lid, flange portion, lip, pop valve and top configuration;

FIG. 3 is an expanded view of the left side of the cross sectional figure illustrated in FIG. 2 and taken about line 2-2 of FIG. 2;

FIG. 4 illustrates a perspective view of a square container with a lid in place and illustrating the corner located extended lips, pop valve and top configuration;

FIG. 5 is a sectional view taken along line 5-5 of FIG. 4 and illustrates further details of the lid, flange portion, lip, pop valve and top configuration;

FIG. 6 is an expanded view of the left side of the cross sectional figure illustrated in FIG. 5 and taken about line 6-6 of FIG. 5; and

FIG. 6 illustrates a round container which uses an acentric or non-constant cross section flange portion to facilitate opening.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The description, construction and operation of the sealing system of the invention will be best illustrated by beginning with reference to FIG. 1, which illustrates a perspective view of a rectangular oblong container 21 including a lid 23 and a base container 25. The base container 25 may include a generally circumferentially outwardly projecting rim 27 which may serve as a reinforcement for the upper part of the base container 25 and as a visual indicator that the lid 23 is fitted in place, by visually exacerbating any displacement from a flat sealed condition. Also seen are a periodic series of vertical reinforcements 29 which project slightly outwardly from the generally vertical extent of the base container 25.

The lid 23 has a number of features. Lid 23 includes a flange portion 31 made of a more flexible material. Flange portion 31 is continuous adjacent the periphery of the lid 23. Into the flange portion 31, a harder plastic portion 33 is fitted and sealed. Sealing may be by ultrasonic welding, fusion, melting, or molecular bonding to name but a few of the methods of permanent joining, especially of a softer material flange portion 31 to the harder plastic portion 33. The harder plastic portion 33 has surface features including a more sharply downwardly angled transition 35 on three sides leading to a generally flat floor 37. At one end of the lid 23, the transition from the flange 31 to the floor 37 is through an angled portion 39. At the end of the lid 23 most closely adjacent the angled portion 39, a lip 41 extends away from a shorter width side of the lid 23. The lip 41 is typically integrally formed with the flange 31 and is therefore made of softer material.

At the center of the generally flat floor 37 is a safety/pop valve assembly 45. The assembly includes a finger well 47 adjacent a flexible member 49 which is mounted into the a portion of the floor 37. The finger well facilitates manual engagement and lifting of the flexible member 49. The flexible member 49 may fit within a flush space so that the top of the floor 37 will have an even, flat profile. In one embodiment, the flexible member may be “spear locked” through a first aperture in the floor 37 at one end of the flexible member 49. The floor 37 may include a second aperture sized to accept a peg shaped projection from the flexible member such that pressure within the container 21 of a pre-determined magnitude can cause the flexible member to “pop” open upon achievement of a pre-determined internal pressure, to allow pressurized gasses to escape from within the container. This is typically the case where the container of food is used in a microwave, and the pressure setting is pre determined based upon the open area of the aperture. The triggering of the pressure relief valve is by expelling the peg shaped projection (not shown in FIG. 1) and causing the flexible member 49 to bend upwardly. Typically the projection does not re-enter the aperture and additional water vapor or air is permitted to continue to escape. In the alternative, the user can open the safety/pop valve assembly 45 manually in advance of heating, to deliberately allow vapor to escape.

Referring to FIG. 2, a section taken along line 2-2 of FIG. 1 illustrates further details of the internals of the container 21. Beginning at the right side of the figure, the lip 41 has an underside surface which extends to a pair of peripherally inwardly directed surfaces including a first beveled surface 53 which leads to an inwardly angled surface 55 which lies adjacent a rim capture underside surface 57. The other side of the rim capture underside surface 57 is bounded by a downwardly directed rim 59.

The lid 23 is shown in place fitted atop the base container 25, but the drawing shows overlap between portions of the first beveled surface 53, inwardly angled surface 55, and an upper wall 61 of the base container 25 above the outwardly projecting rim 27. Upper wall 61 is continuous about the base container 25. This rendering illustrates the degree to which the downward extending portion of the flange portion 31 would extend inwardly if it were not urged outwardly by the upper wall 61. In response to being urged outwardly by the upper wall 61, the downward extending portion of the flange portion 31 exerts sealing pressure on the outside of the upper wall 61.

Note also that the wall 61 is angled outwardly with respect to a floor 63. The wall 61 is shown as generally linear before a curved transition into floor 63, but the wall 61 may be angled only at the uppermost portion, such as above rim 27.

Referring again to the horizontal portion of the flange portion 31, a channel 65 is seen engaging the outer edge of the harder plastic portion 33 of the lid 23. In this configuration, the channel 65 provides three bonding surfaces to the outside edge of the harder plastic portion 33 of the lid 23, including part of an upper surface, an end edge surface and part of a lower surface. In other words, the outside of the harder plastic portion 33 fits within and is bonded into the channel 65.

Also seen is a slight, thickening of the wall 61 just above the outwardly projecting rim 27, with a slight angled portion 69. As can be seen from the structures described thus far for FIG. 2, two structural accommodations are combined in order to enable container 21 to be more easily opened. The provision of an angled portion 39 adjacent the outwardly extending lip 41 enables mechanical advantage to be more easily applied to left off the lid 23 at the more narrow end of the lid 23. First, locating the lip 41 at the narrower portion adds to the focussing of opening energy applied at the lip 41. If the lip 41 were at the wider side of the lid 23, the opening force would be spread along a wider length of material and the material would simply twistably absorb the force to require a greater force to be applied to open the container 21.

The provision of the angled portion 39 provides a longer flexure distance and provides a natural table for downward pressure. Without the angled portion 39, any lifting of the lip 41 would involve a more severe bending moment between the flange portion 31 and the portion of the generally flat floor 37 which would otherwise be immediately adjacent the flange portion 31 which would be present in the absence of angled portion 39. The more gently angled portion 39 thus acts to spread and facilitate the flexure along the length of the lid 23, while at the same time providing a higher surface for giving the hand greater leverage with respect to the lip 41. Without the angled portion 39, the user's hand would tend to curl around the flange portion 31 adjacent the lip 41. Where hot material is within the container 21, the curling of the user's hand around the flange portion 31 increases the chance of burns. The provision of the angled portion 39 enables a stable raised portion which helps the user open the lid 23 with the hand held farther away from the container 21.

Further to the left of the angled portion 39, the finger well 47 is seen. The flexible member 49 can be seen as projecting slightly over the deepest part of the finger well 47. Also can be seen are two projections extending downwardly from the flexible member 49. Farthest from the end overlying the finger well 47, a solid plug 73 sealingly fits through an aperture 75 to solidly and sealingly hold the area of the flexible member 49 immediately surrounding it. Spaced apart from the solid plug 73 and aperture 75 is a vent aperture 77 into which fits an annular cylindrical projection 79. Knowing the materials, tolerances of the vent aperture 77 and annular cylindrical projection 79, as well as the diameter of a vent aperture 77 and annular cylindrical projection 79, the internal pressure within the container 21 which will cause the annular cylindrical projection 79 to be forced through the vent aperture 77 can be easily known. Then, the sizes of the vent aperture 77 and annular cylindrical projection 79 which seals into the vent aperture 77 can be selected to cause the flexible member 49 to open upon the achievement of a predetermined pressure within the container 21.

Referring to the far left side of FIG. 2, as well as referring for the first time to FIG. 3, an expanded view of the relationships taken along section line 3-3 of FIG. 2 illustrates the further details of the interaction between the flange portion 31 and the upper wall 61 of the base container 25. As was mentioned earlier, there is some overlap seen as the angles and positions of the component parts are in the non-stressed position. The main movements of the component parts seen will be largely an angular displacement of the downward portion of the flange portion 31 of about six degrees.

The expanded FIG. 3 also facilitates a discussion of dimensioning as might be appropriate for a small container of from about 15 to 30 centimeters long. The wall 61 of the base container 25 below the outwardly projecting rim 27 may be about two millimeters while the thickness of the wall 61 above the outwardly projecting rim 27 may be about one and a half millimeters. This provides some complementary flexibility to the wall 61 above the outwardly projecting rim 27 so that the angular displacement can be somewhat shared (slightly) with the downwardly extending portion of the flange.

Other dimensions which may preferably be employed include what can now be clearly seen as a vertical or downward web 81 of the flange portion 31 which may have a length of about thirteen and a half centimeters below a above a top or horizontal web 83 of flange portion 31. The width of the horizontal web 83 may be about nine centimeters with the depth of the channel 65 being about two centimeters. As can also be seen, the harder plastic portion 33 has a reduced thickness portion where it enters the channel 65. The main thickness of the harder plastic portion 33 is about two and a third centimeters, but the thickness is reduced at the point of entry to the channel 65 to about one and a third centimeters.

Both the angularity and the provision of angled surfaces contribute to the ease of use of the container 21. The general downward extent of the vertical web 81 with respect to the horizontal web 83 may preferably have an angle α of from about ninety degrees to about ninety six degrees and preferably about ninety three degrees. The general outward angled nature of the flange vertical web 83 may help to contribute to both ease of attachment of the lid 23 to the base container 25, as well as to help the user grasp the underside of vertical web 83 especially where the lid 23 is partially off of the base container 25.

Two other angles seen to the inside of the flange 31 include an angle β that the inwardly angled surface 55 makes with respect to the horizontal web 83, and is about eighty degrees. Put another way, the inwardly angled surface 55 forms an inward ramp having an angle of from about fifteen to about five degrees and preferably about ten degrees from a vertical taken with respect to the horizontal web 83. Since the outside of the vertical web 81 is angled about three degrees away from straight vertical, the inwardly angled surface 55 has an angle of about thirteen degrees taken with respect to the outside of the vertical web 81.

In the Figure, the inwardly angled surface 55 is shown as crossing into, or invading the area occupied by the upper wall 61 when in fact the vertical web 81 would normally be expected to bend outwardly to accommodate the upper wall 61. An angle γ, is taken between the horizontal web 83 (which is not expected to deflect significantly when the lid 23 is fitted onto the base container 25) and the center of the upper wall 61, but taken with respect to the outer surface of upper wall 61 and which may be from about eighty four to about eighty eight degrees but may be more preferably about eighty six degrees. Thus, the upper wall is tilted outward with respect to the vertical of from about two to about six degrees and may be tilted preferably about four degrees. Also, the inwardly angled surface 55 is inwardly angled by about six degrees more than the upper wall 61 would seem to allow and thus with respect to the vertical is inwardly angled by about ten degrees. It is the force created when the horizontal web 81 is flexed outwardly which is brought to bear on the outside of wall 61. Further, this sealing occurs over a height of the outside of the upper wall of about six centimeters. As a result, the inward force is concentrated on the upper most six centimeter depth of the outside of wall 61.

The first beveled surface 53 forms an angle with respect to the inwardly angled surface 55 as shown by indicator δ of from about one hundred thirty four degrees to about one hundred fifty four degrees and preferably about one hundred forty four degrees (meaning that the angle between the face of those surfaces will be between about two hundred six degrees to about two hundred twenty six degrees and preferably about two hundred sixteen degrees). The height of the inwardly angled surface 55 of about five and a half centimeters. The angling of this additional length to the vertical web accomplishes several advantages. First, it facilitates the use of a flange 31 having an inwardly angled first beveled surface 53 for initial contact with the a base container 25 having an outwardly angled upper wall 61 by eliminating the need for the user to stretch the lid 23 about the upper extent of the upper wall 61 like applying a rubber band. Second, the effective vertical angular displacement of first beveled surface 53 as it is brought straight down over the base container 25 is from about sixteen degrees to about thirty six degrees and preferably about twenty six degrees. This gives a force ratio of at least 2:1. This means that any force placed on the lid 23 in the downward direction causes a bending force of twice as much on the flange 31, at least until the transition between the first beveled surface 53 and inwardly angled surface 55 is reached.

Once the transition between the first beveled surface 53 and inwardly angled surface 55 is reached, the inward angular displacement of the inwardly angled surface 55 of six degrees greater than the four degree outward tilt of the upper wall 61 facilitates the ease of further movement. This occurs as the sealing area is increased while the main force near the transition between the transition between the first beveled surface 53 and inwardly angled surface 55 maintains the maximum pressure against the upper wall 61. This produces a sweep sealing action in which a line of maximum sealing is hand, but with significant sealing above the transition between the first beveled surface 53 and inwardly angled surface 55.

Also note the more severe upward and across shape as the generally flat floor 37 of the harder plastic portion 33 makes is transition upwardly and to a horizontal orientation before extending into the channel 65. Compared with the angled portion 39 seen in FIG. 2, any lifting of the horizontal web 81 would encounter more resistance by placing bending pressure over a shorter length away from the flange 31. Thus by comparison, the structure seen at the right of FIG. 2 actually provide an easier structure and method for removal of the lid 23 from the base container 25.

Referring to FIG. 4, a perspective view of a further embodiment of the container previously shown in FIGS. 1-3 is illustrated as a container 91. Container 91 has many of the same features seen on container 21, including lid 23, base container 25. Container 21 also includes its own outwardly projecting rim 27, but as will be shown in subsequent figures is associated with a more prominent and more angled structure similar to the slight angled portion 69 seen with container 21.

Since container 91 is rectangular shaped, the flange portion 31 has a pair of projecting lips 93 at opposite corners of the lid 23. This gives a more concentrated lift area even though no part of the generally flat floor 37 of lid 23 of container 91 is seen.

Referring to FIG. 5, a cross sectional view taken along line 5-5 of FIG. 3 is shown. Many of the same elements which appeared in FIG. 2 are also seen in FIG. 5. Notable differences are the provision of a severely angled portion or shelf 95 which si horizontally continuous with the rim 27. Upper wall 61 is again present, but it extends upwardly from the shelf 95. A base container wall 97 is seen as extending downwardly from the innermost end of the shelf 95, whereas the upper wall 61 extends upward from a point slightly off center in a direction toward the outside of the shelf 95. In effect, the rim 27 forms a thickened outside of the shelf 95 beyond the point at which upper wall 61 rises from the shelf 95. The use of a shelf 95 as a transition member better allows the outward tilt of the upper wall 61 to exist independent of the tilt of the base container wall 97. Further, the shelf structure 95 allows for additional reinforcement of the base container 25.

Referring to FIG. 6 an expanded portion of container 91 is seen taken along line 6-6 of FIG. 5. Most of the structures and angle indications are the same, but it should be noted that the rim capture underside surface 57 is slightly narrower, and that the transition of the generally flat floor 37 from its main extent and into a position where it inters the channel 65 is more abrupt.

Referring to FIG. 7 a top view of a container 101 has a lid 103 overlying a base container having a lip 105 with a circular flat floor 107 which is fitted into a flange portion 109 which has a cross sectional width which varies from wide to narrow. The cross sectional width is widest at the midpoint of a lip 111 which may be integrally formed with respect to the flange portion 109. The cross sectional width is narrowest at the opposite side of the midpoint of lip 111 of lid 103.

Instead of providing a raised or gently sloping angled portion 39 as was seen in FIG. 1 to facilitate manual opening, an additional width of flange portion 109 provides both an additional measure of raised surface and an additional length of flexible material to facilitate ease of opening and closing. Instead of simply providing a platform from which the thumb can lift the outside material, as was the case with angled portion 39, the provision of both an extended platform co-existent with the level of the flange portion 109 and the provision of an additional peripheral width of flexible flange material 109 to ease manipulation.

While the present invention has been described in terms of a system and method for providing controlled capture of a lid and base of a sealed container, one skilled in the art will realize that the structure and techniques of the present invention can be applied to many structures, including any structure or technique where an efficient sealing is to be had with a container lid and base and which is stable, and can be operated with less force and more sealing.

Although the invention has been derived with reference to particular illustrative embodiments thereof, many changes and modifications of the invention may become apparent to those skilled in the art without departing from the spirit and scope of the invention. Therefore, included within the patent warranted hereon are all such changes and modifications as may reasonably and properly be included within the scope of this contribution to the art. 

1. A sealable container comprising: a base having an upper wall about the upper periphery of said base; a lid including: a flange portion adjacent and outer periphery of said lid and including at least a pair of peripherally inwardly facing surfaces angled with respect to each other; and a floor portion within said flange portion.
 2. The sealable container as recited in claim 1 and wherein said peripherally inwardly facing surfaces angled with respect to each other includes an inwardly angled portion and an adjacent beveled surface.
 3. The sealable container as recited in claim 1 and wherein an inward angle normal to a main planar extent of said lid of said inwardly angled portion is less than an outward angle of said adjacent beveled surface.
 4. The sealable container as recited in claim 2 and wherein said peripherally inwardly facing inwardly angled portion has an angular inclination of from about fifteen to about five degrees from a vertical taken with respect to line normal to a main planar extent of said lid.
 5. The sealable container as recited in claim 4 wherein said peripherally inwardly facing inwardly angled portion has an angular inclination of about ten degrees from a vertical taken with respect to a main planar extent of said lid.
 6. The sealable container as recited in claim 1 wherein said base includes a peripherally outwardly directed rim 27 below said upper wall.
 7. The sealable container as recited in claim 1 wherein said flange portion includes a horizontal web and wherein said horizontal web and a vertical web, and wherein an underside of said horizontal web has a downwardly directed rim and a rim capture underside surface between said downwardly directed rim and said vertical web.
 8. The sealable container as recited in claim 1 wherein said flange portion includes a peripherally inwardly directed channel, and wherein said floor portion is connected to said flange portion into said channel.
 9. The sealable container as recited in claim 1 wherein said upper wall of said base is tilted outwardly from about two to about six degrees.
 10. The sealable container as recited in claim 9 wherein said upper wall of said base is tilted outwardly with respect to the vertical of about four degrees.
 11. The sealable container as recited in claim 1 wherein said vertical web has an angle with respect to said horizontal web of from about ninety degrees to about ninety six degrees.
 12. The sealable container as recited in claim 11 wherein said vertical web has an angle with respect to said horizontal web of about ninety three degrees.
 13. The sealable container as recited in claim 1 wherein said lid includes a safety valve assembly which opens when the pressure inside said sealable container exceeds a predetermined pressure.
 14. The sealable container as recited in claim 1 wherein said flange portion of said lid includes an outwardly projecting lip and where said lid includes a raised, angled portion opposite said lip. 